If you are, do it right. There was no shamrock. That wasn't something the Japanese used culturally. That's been mis-identified since forever and the poor 1-reference has a very off-angle shot of it. Do some searching on it and you'll find some informative discussions on the matter and what it most likely was a depiction of. We've even discussed it on these forums long ago.
It wasn't a shamrock/clover. IMO it wasn't even colored. Looking at the photo it looks like a white outline painted by hand but not filled in. That is my interpretation based on the very unhelpful photo.
Also if I recall the plane in question was one of the few examples on record of a Ki-61-II, which had (theoretically) hundreds of horsepower more than the Ki-61-I. The engines were unreliable at that point -- one reason they made the Ki-100 -- and the few examples that made it weren't well regarded. You'll also note that the 20mm cannon ports are faired over and the plane was only armed with 2x wing machine guns.
Overall IMO it doesn't fit our Ki-61 model from AH, and seeing as it was a wrecked fuselage in a field of wrecked fuselages there's no telling if it ever saw combat or made it off the ground before bing scrapped. Ichikawa was known for taking previous kill claims and painting them on new rides, so those kill marks don't mean he earned them in that plane, specifically. He could have had it painted but never got to use it.
